IEEE/ACM Transactions on Networking最新文献

{"title":"OBMA: Scalable Route Lookups With Fast and Zero-Interrupt Updates","authors":"Chuwen Zhang;Yong Feng;Haoyu Song;Ying Wan;Wenquan Xu;Bin Liu","doi":"10.1109/TNET.2024.3446689","DOIUrl":"https://doi.org/10.1109/TNET.2024.3446689","url":null,"abstract":"Software-based IP route lookup is a key component for packet forwarding in Software Defined Networks. Running lookup algorithms on commodity CPUs is flexible and scalable, which shows advantages on cost and power consumption over the hardware-based forwarding engines. However, dynamic network functions and services make route updates more frequent than ever. Existing algorithms often fall short of the incremental update requirements. In this paper, we propose the Overlay BitMap Algorithm (OBMA), which contains several variations, to support extraordinary update performance while maintaining the highest-in-class lookup speed and storage efficiency. Starting from the basic OBMA_B, we develop two variations with different tradeoffs for different application scenarios. OBMA_L supports faster lookups than OBMA_B at a small cost of update speed. OBMA_S achieves better storage efficiency than OBMA_B at a small cost of lookup throughput. We run our algorithms on a commodity CPU and evaluate them with real-world route tables and traces. The experiments show that OBMA achieves the lowest memory footprint, the highest update speed, and over 200 Mpps lookup throughput. Specifically, OBMA_S reduces the memory footprint to 3.98 bytes/prefix which is 25.33% smaller that of the state-of-the-art Poptrie; OBMA_L supports 252.02 Mpps lookup throughput with a single thread, and more than 600 Mpps with multiple parallel threads in a single CPU, significantly outperforming the state-of-the-art Poptrie and SAIL; OBMA_B supports updates at a rate of 14.58M updates/s which is 15 times faster than Poptrie. The tests show that the update process has little interference with the lookup process for OBMA, and achieves zero-interrupt to lookups with multiple threads.","PeriodicalId":13443,"journal":{"name":"IEEE/ACM Transactions on Networking","volume":"32 6","pages":"4842-4854"},"PeriodicalIF":3.0,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142858920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mobile IP Geolocation Based on District Anchor Without Cooperation of Users or Internet Service Providers","authors":"Ruixiang Li;Xiaoyun Yuan;Meijuan Yin;Xiangyang Luo","doi":"10.1109/TNET.2024.3471335","DOIUrl":"https://doi.org/10.1109/TNET.2024.3471335","url":null,"abstract":"Mobile IP geolocation aims to obtain a mobile device’s geographic location by IP. This technology is widely used in preventing financial risk, investigating cybercrime, and delivering targeted information. Currently, there are three types of IP geolocation: based on cooperation, querying in database, or network measurement. However, since restricted cooperation, low-reliability databases, and unresponsive mobile IPs, existing technologies are hard to geolocate fine-grained location of mobile IP. In this paper, we propose the concept of district anchor, and propose a non-cooperative mobile IP geolocation scheme, including three parts: acquiring district anchors by clustering, evaluating the reliability of district anchors, and geolocating mobile IPs. We also give implemented approach of this scheme. Instead of using existing clustering algorithms treating IPs and geolocations in no particular order, we propose two-stages clustering algorithm (IPG2C) to acquire district anchors, and establish reliability evaluation mechanism by IP distribution and spatial distribution of cluster. Eventually, using obtained reliable district anchors, we use “subnet geolocation” strategy to geolocate mobile IPs. The experimental results in 10 cities show that: 1) our scheme can be used to geolocate mobile IPs without cooperation; 2) the mean geolocation error is 12.47km, where precision of 56.67% of mobile IPs is street-level and minimum error is only 13m; 3) that the mean geolocation error of the anchor-based method is smaller than that of the landmark-based method; 4) compared with 13 clustering algorithms (e.g., K-Means++, Mean Shift, DBSCAN, and GMM), mean geolocation error using IPG2C’s district anchors is reduced by 26.62%~50.77%.","PeriodicalId":13443,"journal":{"name":"IEEE/ACM Transactions on Networking","volume":"32 6","pages":"5507-5523"},"PeriodicalIF":3.0,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142858965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluid-Shuttle: Efficient Cloud Data Transmission Based on Serverless Computing Compression","authors":"Rong Gu;Shulin Wang;Haipeng Dai;Xiaofei Chen;Zhaokang Wang;Wenjie Bao;Jiaqi Zheng;Yaofeng Tu;Yihua Huang;Lianyong Qi;Xiaolong Xu;Wanchun Dou;Guihai Chen","doi":"10.1109/TNET.2024.3402561","DOIUrl":"https://doi.org/10.1109/TNET.2024.3402561","url":null,"abstract":"Nowadays, there exists a lot of cross-region data transmission demand on the cloud. It is promising to use serverless computing for data compressing to save the total data size. However, it is challenging to estimate the data transmission time and monetary cost with serverless compression. In addition, minimizing the data transmission cost is non-trivial due to the enormous parameter space. This paper focuses on this problem and makes the following contributions: 1) We propose empirical data transmission time and monetary cost models based on serverless compression. It can also predict compression information, e.g., ratio and speed using chunk sampling and machine learning techniques. 2) For single-task cloud data transmission, we propose two efficient parameter search methods based on Sequential Quadratic Programming (SQP) and Eliminate then Divide and Conquer (EDC) with proven error upper bounds. Besides, we propose a parameter fine-tuning strategy to deal with transmission bandwidth variance. 3) Furthermore, for multi-task scenarios, a parameter search method based on dynamic programming and numerical computation is proposed. We have implemented the system called Fluid-Shuttle, which includes straggler optimization, cache optimization, and the autoscaling decompression mechanism. Finally, we evaluate the performance of Fluid-Shuttle with various workloads and applications on the real-world AWS serverless computing platform. Experimental results show that the proposed approach can improve the parameter search efficiency by over \u0000<inline-formula> <tex-math>$3times $ </tex-math></inline-formula>\u0000 compared with the state-of-art methods and achieves better parameter quality. In addition, our approach achieves higher time efficiency and lower monetary cost compared with competing cloud data transmission approaches.","PeriodicalId":13443,"journal":{"name":"IEEE/ACM Transactions on Networking","volume":"32 6","pages":"4554-4569"},"PeriodicalIF":3.0,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142859215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"eMPTCP: A Framework to Fully Extend Multipath TCP","authors":"Dian Shen;Bin Yang;Junxue Zhang;Fang Dong;John C. S. Lui","doi":"10.1109/TNET.2024.3469396","DOIUrl":"https://doi.org/10.1109/TNET.2024.3469396","url":null,"abstract":"MPTCP provides the basic multipath support for network applications to deliver high throughput and robust communication. However, the original MPTCP is designed with limited extensibility. Various research works have tried to extend MPTCP to attain better performance or richer functionalities. These existing approaches either modify the kernel implementation of MPTCP, which involve considerable engineering efforts and may accidentally introduce safety issues, or control MPTCP via userspace tools, which suffer from restricted functionality support. To address this issue, we propose eMPTCP, an easy-to-use framework to fully extend MPTCP without safety risks. Internally, eMPTCP has a modular and pluggable model which allows operators to specify a comprehensive MPTCP extension as a chain of sub-policies. eMPTCP further enforces the policies through packet header manipulations. To ensure safety, eMPTCP is implemented using eBPF. Despite the stringent constraints of eBPF, we show that it is possible to implement an elaborated framework for a fully extensible MPTCP. Through verifying MPTCP in a number of real-world cases and extensive experiments, we show that eMPTCP is able to support a wide range of MPTCP extensions, while the overhead of eMPTCP operations in the kernel is in the scale of nanosecond, and the extra processing time accounts for only about 0.63% of flows’ transmission time.","PeriodicalId":13443,"journal":{"name":"IEEE/ACM Transactions on Networking","volume":"32 6","pages":"5459-5474"},"PeriodicalIF":3.0,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142858963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distributed Stable Multi-Source Dynamic Broadcasting for Wireless Multi-Hop Networks Under SINR-Based Adversarial Channel Jamming","authors":"Xiang Tian;Baoxian Zhang;Cheng Li;Jiguo Yu","doi":"10.1109/TNET.2024.3470649","DOIUrl":"https://doi.org/10.1109/TNET.2024.3470649","url":null,"abstract":"Disseminating continuous packet flows injected at multiple location-random source nodes to all network nodes, known as the multi-source dynamic global broadcast problem, is a fundamental building block for wireless multi-hop networks to run smoothly and efficiently. Previous studies on dynamic global broadcast all assume reliable communications. However, in realistic wireless networks, there exist unpredictable transmission failures caused by the randomized signal interference from uncorrelated wireless networks sharing the same spectrum or even malicious attackers. In this paper, by integrating the Signal-to-Interference-plus-Noise-Ratio (SINR) model, multi-channel communication mode, and randomized malicious channel jamming controlled by an adaptive adversary, we present an SINR-based adversarial channel jamming model to capture the unpredictable transmission failures in a wireless multi-hop network. We first propose a distributed Jamming-resilient Multi-source Static Broadcast (JMSB) algorithm based on random channel selection and message transmissions for multi-hop wireless networks under the above SINR-based adversarial channel jamming model. We then propose a distributed stable Jamming-resilient Multi-source Dynamic Broadcast (JMDB) algorithm which iterates JMSB repeatedly and efficiently in a two-stage manner. We derive the maximum supportable broadcast throughput of JMDB under the stability guarantee, i.e., the expected boundedness on the queue length of each network node and expected broadcast latency for each injected packet. Simulation results shows the stability and throughput efficiency of our proposed JMDB algorithm.","PeriodicalId":13443,"journal":{"name":"IEEE/ACM Transactions on Networking","volume":"32 6","pages":"5356-5371"},"PeriodicalIF":3.0,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142859325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scout Sketch+: Finding Both Promising and Damping Items Simultaneously in Data Streams","authors":"Guoju Gao;Tianyu Ma;He Huang;Yu-E Sun;Haibo Wang;Yang Du;Shigang Chen","doi":"10.1109/TNET.2024.3469196","DOIUrl":"https://doi.org/10.1109/TNET.2024.3469196","url":null,"abstract":"Data stream processing holds great potential value in lots of practical application scenarios. This paper studies two new but important patterns for items in data streams, called promising and damping items. The promising items mean that the frequencies of an item in multiple continuous time windows show an upward trend overall, while a slight decrease in some of these windows is allowed. In contrast to promising items exhibiting an increasing trend, the definition of damping items indicates a decreasing trend. Many applications can benefit from the property of promising or damping items, e.g., monitoring latent attacks in computer networks, pre-adjusting bandwidth allocation in communication channels, detecting potential hot events/news, or finding topics that gradually lose momentum in social networks. We first introduce how to accurately find promising items in data streams in real-time under limited memory space. To this end, we propose a novel structure named Scout Sketch, which consists of Filter and Finder. Filter is devised based on the Bloom filter to eliminate the ungratified items with less memory overload; Finder records some necessary information about the potential items and detects the promising items at the end of each time window, where we propose some tailor-made detection operations. We then enhance Scout Sketch (called Scout Sketch+) to adaptively detect both types of promising and damping items simultaneously. Finally, we conducted extensive experiments on four real-world datasets, which show that the F1 Score and throughput of Scout Sketch(+) are about 2.02 and 5.61 times that of the compared solutions. All source codes are available at Github (\u0000<uri>https://github.com/Aoohhh/ScoutSketch</uri>\u0000).","PeriodicalId":13443,"journal":{"name":"IEEE/ACM Transactions on Networking","volume":"32 6","pages":"5491-5506"},"PeriodicalIF":3.0,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142858960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LFVeri: Network Configuration Verification for Virtual Private Cloud Networks","authors":"Kun Wang;Chengcheng Zhao;Jinpei Chu;Yiping Shi;Jianyuan Lu;Biao Lyu;Shunmin Zhu;Peng Cheng;Jiming Chen","doi":"10.1109/TNET.2024.3469386","DOIUrl":"https://doi.org/10.1109/TNET.2024.3469386","url":null,"abstract":"The Virtual Private Cloud (VPC) service enables users to configure shared resources within public clouds on demand, providing isolation between users. However, configuring the VPC network is a complex and error-prone task, and misconfiguration has been the leading cause of cloud network security issues. The large number of complex network components and configurations makes it difficult to perform scalable, efficient, and accurate fault verification of the network behavior. To address this issue, we design a comprehensive and automated fault diagnosis and localization tool, called \u0000<monospace>LFVeri</monospace>\u0000, which is built upon an innovative modular network model that accurately captures the logic functions of real components within VPC networks, and propose eleven functions to verify network reachability and security requirements. We conduct performance testing of \u0000<monospace>LFVeri</monospace>\u0000 on various datasets and compared it with other verification tools. The experiments show that \u0000<monospace>LFVeri</monospace>\u0000 outperforms in modeling and analyzing real VPC scenarios while also possessing the fastest verification speed. It can model and analyze large VPC networks with tens of thousands of components and millions of configuration rules in less than half an hour.","PeriodicalId":13443,"journal":{"name":"IEEE/ACM Transactions on Networking","volume":"32 6","pages":"5475-5490"},"PeriodicalIF":3.0,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142858962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Social-Aware Clustered Federated Learning With Customized Privacy Preservation","authors":"Yuntao Wang;Zhou Su;Yanghe Pan;Tom H. Luan;Ruidong Li;Shui Yu","doi":"10.1109/TNET.2024.3379439","DOIUrl":"https://doi.org/10.1109/TNET.2024.3379439","url":null,"abstract":"A key feature of federated learning (FL) is to preserve the data privacy of end users. However, there still exist potential privacy leakage in exchanging gradients under FL. As a result, recent research often explores the differential privacy (DP) approaches to add noises to the computing results to address privacy concerns with low overheads, which however degrade the model performance. In this paper, we strike the balance of data privacy and efficiency by utilizing the pervasive social connections between users. Specifically, we propose SCFL, a novel Social-aware Clustered Federated Learning scheme, where mutually trusted individuals can freely form a social cluster and aggregate their raw model updates (e.g., gradients) inside each cluster before uploading to the cloud for global aggregation. By mixing model updates in a social group, adversaries can only eavesdrop the social-layer combined results, but not the privacy of individuals. As such, SCFL considerably enhances model utility without sacrificing privacy in a low-cost and highly feasible manner. We unfold the design of SCFL in three steps. i) Stable social cluster formation. Considering users’ heterogeneous training samples and data distributions, we formulate the optimal social cluster formation problem as a federation game and devise a fair revenue allocation mechanism to resist free-riders. ii) Differentiated trust-privacy mapping. For the clusters with low mutual trust, we design a customizable privacy preservation mechanism to adaptively sanitize participants’ model updates depending on social trust degrees. iii) Distributed convergence. A distributed two-sided matching algorithm is devised to attain an optimized disjoint partition with Nash-stable convergence. Experiments on Facebook network and MNIST/CIFAR-10 datasets validate that our SCFL can effectively enhance learning utility, improve user payoff, and enforce customizable privacy protection.","PeriodicalId":13443,"journal":{"name":"IEEE/ACM Transactions on Networking","volume":"32 5","pages":"3654-3668"},"PeriodicalIF":3.0,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142447182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combining Capacity and Length: Finding Connectivity Bottleneck in a Layered Network","authors":"Peng Zhang","doi":"10.1109/TNET.2024.3466522","DOIUrl":"https://doi.org/10.1109/TNET.2024.3466522","url":null,"abstract":"Computer networks are often multi-layered. For simplicity, let us focus on two-layered networks with logical layer and physical layer. Such a network can be modeled as a labeled graph \u0000<inline-formula> <tex-math>$G = (V, E)$ </tex-math></inline-formula>\u0000 with a label set \u0000<inline-formula> <tex-math>$L = {ell _{1}, ell _{2}, {dots }, ell _{q} }$ </tex-math></inline-formula>\u0000, in which each edge (denotes logical connection) \u0000<inline-formula> <tex-math>$e in E$ </tex-math></inline-formula>\u0000 has a label (denotes physical link) \u0000<inline-formula> <tex-math>$ell (e)$ </tex-math></inline-formula>\u0000 from L. The key issue is that different edges may have the same label. In the weighted minimum Label s-t Cut problem, we are given a labeled graph \u0000<inline-formula> <tex-math>$G=(V,E)$ </tex-math></inline-formula>\u0000 with label set L, where each label \u0000<inline-formula> <tex-math>$ell $ </tex-math></inline-formula>\u0000 has a nonnegative weight \u0000<inline-formula> <tex-math>$w_{ell } $ </tex-math></inline-formula>\u0000, a source \u0000<inline-formula> <tex-math>$s in V$ </tex-math></inline-formula>\u0000 and a sink \u0000<inline-formula> <tex-math>$t in V$ </tex-math></inline-formula>\u0000. The problem asks to find a minimum weight label subset \u0000<inline-formula> <tex-math>$L'$ </tex-math></inline-formula>\u0000 (called a label s-t cut) such that the removal of all edges with labels in \u0000<inline-formula> <tex-math>$L'$ </tex-math></inline-formula>\u0000 disconnects s and t. Label s-t cut depicts the connectivity bottleneck of a layered network. It is a natural generalization of the edge connectivity of a graph. In this paper, we provide an approximation algorithm for the weighted Label s-t Cut problem with ratio \u0000<inline-formula> <tex-math>$O(n^{2/3})$ </tex-math></inline-formula>\u0000, where n is the number of vertices. This is the first approximation algorithm for the problem whose ratio is given in terms of n. The key point of the algorithm is a mechanism to interpret label weight on an edge as both its length (as in the Shortest s-t Path problem) and capacity (as in the Min s-t Cut problem). Experiments on random graphs show that the algorithm has also good practical performance.","PeriodicalId":13443,"journal":{"name":"IEEE/ACM Transactions on Networking","volume":"32 6","pages":"5430-5439"},"PeriodicalIF":3.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142859216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"QUIRL: Flexible QUIC Loss Recovery for Low Latency Applications","authors":"François Michel;Olivier Bonaventure","doi":"10.1109/TNET.2024.3453759","DOIUrl":"https://doi.org/10.1109/TNET.2024.3453759","url":null,"abstract":"A growing number of Internet applications require low latency. Unfortunately, most of these applications cannot use the rich features of the QUIC protocol since it only uses retransmissions to cope with packet losses. We propose, implement and evaluate QUIRL, a revisit of the QUIC loss recovery mechanism. QUIRL relies on Forward Erasure Correction (FEC) only if it is needed by the application’s latency requirements and uses classical retransmissions otherwise. We implement QUIRL and evaluate its performance for real-time video and HTTP/3. Compared to previous works adding FEC to QUIC, QUIRL is the first to be evaluated with and obtain significant performance improvements for popular applications over real lossy networks. Our evaluation shows that for video QUIRL improves the video quality while meeting strict delay requirements. For HTTP/3 transfers, QUIRL efficiently reduces the tail latency when packet losses occur without causing harm when there are no losses. We confirm these results using emulation over a wide ranges of bandwidth, delays and loss scenarios. We release our QUIRL implementation to encourage other researchers and industry to explore in more details the use of FEC in QUIC.","PeriodicalId":13443,"journal":{"name":"IEEE/ACM Transactions on Networking","volume":"32 6","pages":"5204-5215"},"PeriodicalIF":3.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142859202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}